RF Accident Security

In this project we will control the accidents on road. We are making collision system. When any car or any thing come infront of car it will wirelessly give signal to nearest receiver.

We will use RF technology for this purpose.

RF remote control which is built using HT12E and HT12D chips. The remote control is built using RF encoder chip HT12E that will generate different codes. These codes will be transmitted by 434 MHz RF transmitter. At the receiving side these codes will be received by 434 MHz RF receiver and decoded by RF decoder chip HT12D.

In this project we show that how we design a RF information transfer  . In this project we use two RF module for wireless data transfer.In this project we use 89s52 microcontroller as a main processor.. This controller is basically a  40 pin ic. In this project we use two sensor also.ROM of 89s52 is 8k and ram is 256 byte. We are using 16*2 lcd in this project. Lcd is connected to port 0 which will display the no. of vehicle . we are using counter in programming to show no. of accidents in that area. So that solutions can be found out to avoid these accidents. We will use buzzer to alert about accident on receiver side. A rf tag transmitter will be provided to each vehicle for vehicle identification. In case of any accident it will transmit its ID. On receiver side RF module will give signal to microcontroller. Microcontroller is decision maker here and informer to person on duty.It will give data to LCD , buzzer and LED’s. we will also use four LEDs to show accidents for immediate action.

These sensor are connected to the port p3.4 and port p3.5



Pin no 40 is connected to the positive supply. In this project we provide a 5 volt dc power supply. This power supply is truly regulated power supply. Pin no 20 is connected to the negative supply. Here we supply a negative voltage on this pin. Crystal is connected to the pin no 18 and 19 of the microcontroller. Crystal provide a clock signal to run the vehicle and process all the internal requirement of the  circuit. We use two sensor and these two sensor are connected to the p3.4 and p3.5 of the microcontroller.For the regulated power supply we use ic 7805 as a regulator to provide a fix 5 volt power supply.

In this project we will make a transmitter for RF data transmission. Pin no 1of RF tx module is ground . second is for data , third for VCC and fourth for antenna Transmitter


We transmitter whole project in few steps:

RF transmitter

  • RF module
  • Encoder circuit

RF receiver

  • Rf receiver
  • Decoder
  • Microcontroller circuit
  • Visual indication- LCD and LEDs
  • Audio alert- buzzer





Block diagram transmitter








Block Diagram of receiver


























What is Embedded System?

An embedded system is some combination of computer hardware and software, either fixed in capability or programmable, that is specifically designed for a particular function. Industrial machines, automobiles, medical equipment, cameras, household appliances, airplanes, vending machines and toys (as well as the more obvious cellular phone and PDA) are among the myriad possible hosts of an embedded system. Embedded systems that are programmable are provided with programming interfaces, and embedded systems programming is a specialized occupation.

Certain operating systems or language platforms are tailored for the embedded market, such as Embedded Java and Windows XP Embedded. However, some low-end consumer products use very inexpensive microprocessors and limited storage, with the application and operating system both part of a single program. The program is written permanently into the system’s memory in this case, rather than being loaded into RAM (random access memory) like programs on a personal computer.



A microcontroller (often abbreviated MCU) is a single computer chip that executes a user program, normally for the purpose of controlling some device hence the name microcontroller.

A microcontroller is differed from microprocessor in many ways. Basically microprocessors are the devices which can process huge amount of data. A microprocessor can’t do anything on it own. Even to light a led a microprocessor needs minimum of a ROM, RAM, Latch, Address decoders, PORT controllers. But for the same application if you take a microcontroller you barely need a crystal and some capacitors.

So from this you can understand how versatile the microcontroller is.



  •  Compatible with MCS®-51 Products
  • 8K Bytes of In-System Programmable (ISP) Flash Memory – Endurance: 10,000 Write/Erase Cycles
  • 4.0V to 5.5V Operating Range
  •  Fully Static Operation: 0 Hz to 33 MHz
  •  Three-level Program Memory Lock
  •  256 x 8-bit Internal RAM
  •  32 Programmable I/O Lines
  •  Three 16-bit Timer/Counters
  •  Eight Interrupt Sources
  •  Full Duplex UART Serial Channel
  •  Low-power Idle and Power-down Modes
  •  Interrupt Recovery from Power-down Mode
  •  Dual Data Pointer
  •  Power-off Flag
  •  Fast Programming Time
  •  Flexible ISP Programming (Byte and Page Mode)




The AT89S52 is a low-power, high-performance CMOS 8-bit microcontroller with 4K bytes of In-System Programmable Flash memory. The device is manufactured using Atmel’s high-density nonvolatile memory technology and is compatible with the industry-standard 80C51 instruction set and pin out. The on-chip Flash allows the program memory to be reprogrammed in-system or by a conventional nonvolatile memory pro-grammar. By combining a versatile 8-bit CPU with In-System Programmable Flash on a monolithic chip, the Atmel AT89S52 is a powerful microcontroller which provides a highly-flexible and cost-effective solution to many embedded control applications.


Component List
S.No. Item Quantity Rate/Unit
1 MCU 89C051 0 80
RF module 1 600
HT12E  1  35
IC91214 1 25
3 IC4049 0 25
4 IC8870 1 40
5 IC555 0 10
6 IC817 1 15
7 IC3021 0 15
Push to On Sw 3 12
10 FLUX 1 10
12 TR548 2 2
13 TR558 0 2
1000µf 2 10
100µf 1 5
470µf 4 5
16 DIODES 8 1
17 LED 8 1
Crystal 12MHz 2 25
18 IC BASE 3 5
IF set 120 1
19 IC 7805 Volt. Reg 2 15
21 SOCKETS 3 10
22 RELAY 9V 3 25
23 MILER CAP 5 3
24 CRYSTAL 3.579545 2 20
25 IC136 2 15
26 HOLDER 2 10
27 PLY BOARD 1 100
28 TAPE ROLL 1 10
29 Copper Clad Board 1 100
30 FeCl3 1 100
31 ZENER 0 3
Screws/bolt 2 2
Betteies 1 15